Cartier-Bresson achieved international recognition for his coverage of Gandhi's funeral in India in 1948 and the last (1949) stage of the Chinese Civil War. He covered the last six months of the Kuomintang administration and the first six months of the Maoist People's Republic. He also photographed the last surviving Imperial eunuchs in Beijing, as the city was falling to the communists. From China, he went on to Dutch East Indies (now Indonesia), where he documented the gaining of independence from the Dutch. Photograph of Alberto Giacometti by Henri Cartier-Bresson.

In 1952, Cartier-Bresson published his book Images à la sauvette, whose English edition was titled The Decisive Moment. It included a portfolio of 126 of his photos from the East and the West. The book's cover was drawn by Henri Matisse. For his 4,500-word philosophical preface, Cartier-Bresson took his keynote text from the 17th century Cardinal de Retz: "Il n'y a rien dans ce monde qui n'ait un moment decisif" ("There is nothing in this world that does not have a decisive moment"). Cartier-Bresson applied this to his photographic style. He said: "Photographier: c'est dans un même instant et en une fraction de seconde reconnaître un fait et l'organisation rigoureuse de formes perçues visuellement qui expriment et signifient ce fait" ("Photography is simultaneously and instantaneously the recognition of a fact and the rigorous organization of visually perceived forms that express and signify that fact").

Both titles came from publishers. Tériade, the Greek-born French publisher whom Cartier-Bresson idolized,[peacock term] gave the book its French title, Images à la Sauvette, which can loosely be translated as "images on the run" or "stolen images." Dick Simon of Simon & Schuster came up with the English title The Decisive Moment. Margot Shore, Magnum's Paris bureau chief, did the English translation of Cartier-Bresson's French preface.

"Photography is not like painting," Cartier-Bresson told the Washington Post in 1957. "There is a creative fraction of a second when you are taking a picture. Your eye must see a composition or an expression that life itself offers you, and you must know with intuition when to click the camera. That is the moment the photographer is creative," he said. "Oop! The Moment! Once you miss it, it is gone forever."

Cartier-Bresson held his first exhibition in France at the Pavillon de Marsan in the Louvre in 1955.